Airplane seats are currently fitted with many elements movable relatively to each other under the action of electrically controlled actuators. In order to ensure the comfort of the passengers, and to make sure that the seat will not hit elements of the cabin, such as the floor, the seat comprises a computer able to continuously determine the position of certain particular points of the seat and notably the end points of the latter.
In order to ensure this computation, each actuator is fitted with a sensor allowing its position to be known. This sensor is for example formed with a potentiometer or a coding wheel. It is positioned between two movable portions of the actuator.
From the position of each actuator and from knowledge of the geometry of the seat, the computer determines the position of each element of the seat, and of particular points of the latter.